From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hollis Blanchard Subject: Re: _text vs _start Date: Wed, 03 Jan 2007 15:45:39 -0600 Message-ID: <1167860740.6100.57.camel@basalt> References: Reply-To: Hollis Blanchard Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel , Magnus Damm , xen-ppc-devel List-Id: xen-devel@lists.xenproject.org On Wed, 2007-01-03 at 21:32 +0000, Keir Fraser wrote: > On 3/1/07 9:22 pm, "Hollis Blanchard" wrote: > > > On Wed, 2007-01-03 at 15:07 -0600, Hollis Blanchard wrote: > >> Given that you do arithmetic with _end, can you explain why you're not > >> using _start, which is a standard symbol provided by the default linker > >> script? > > > > My mistake; _start of course isn't a linker script symbol at all, but > > rather the entry point code. > > There is an unnecessary disagreement among architectures over what symbols > should be used to mark section and image boundaries. We could reasonably > agree on at least _start/_end and _stext/_etext I think. This would allow > functions like is_kernel_text() to become generic, and make it obvious which > labels kexec should be using. Sounds great to me. PowerPC already arranges for _start to be at the very beginning of .text, which is at the beginning of the first PT_LOAD segment... so the end result is that the address of _start is the same as our link address. We also provide _etext, and _end, but not _stext (currently). -- Hollis Blanchard IBM Linux Technology Center